[linux-block.git] / net / netfilter / xt_CT.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 * Copyright (c) 2010 Patrick McHardy <kaber@trash.net>
 */
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/module.h>
#include <linux/gfp.h>
#include <linux/skbuff.h>
#include <linux/netfilter_ipv4/ip_tables.h>
#include <linux/netfilter_ipv6/ip6_tables.h>
#include <linux/netfilter/x_tables.h>
#include <linux/netfilter/xt_CT.h>
#include <net/netfilter/nf_conntrack.h>
#include <net/netfilter/nf_conntrack_l4proto.h>
#include <net/netfilter/nf_conntrack_helper.h>
#include <net/netfilter/nf_conntrack_ecache.h>
#include <net/netfilter/nf_conntrack_timeout.h>
#include <net/netfilter/nf_conntrack_zones.h>

static inline int xt_ct_target(struct sk_buff *skb, struct nf_conn *ct)
{
	/* Previously seen (loopback)? Ignore. */
	if (skb->_nfct != 0)
		return XT_CONTINUE;

	if (ct) {
		refcount_inc(&ct->ct_general.use);
		nf_ct_set(skb, ct, IP_CT_NEW);
	} else {
		nf_ct_set(skb, ct, IP_CT_UNTRACKED);
	}

	return XT_CONTINUE;
}

static unsigned int xt_ct_target_v0(struct sk_buff *skb,
				    const struct xt_action_param *par)
{
	const struct xt_ct_target_info *info = par->targinfo;
	struct nf_conn *ct = info->ct;

	return xt_ct_target(skb, ct);
}

static unsigned int xt_ct_target_v1(struct sk_buff *skb,
				    const struct xt_action_param *par)
{
	const struct xt_ct_target_info_v1 *info = par->targinfo;
	struct nf_conn *ct = info->ct;

	return xt_ct_target(skb, ct);
}

static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
{
	if (par->family == NFPROTO_IPV4) {
		const struct ipt_entry *e = par->entryinfo;

		if (e->ip.invflags & IPT_INV_PROTO)
			return 0;
		return e->ip.proto;
	} else if (par->family == NFPROTO_IPV6) {
		const struct ip6t_entry *e = par->entryinfo;

		if (e->ipv6.invflags & IP6T_INV_PROTO)
			return 0;
		return e->ipv6.proto;
	} else
		return 0;
}

static int
xt_ct_set_helper(struct nf_conn *ct, const char *helper_name,
		 const struct xt_tgchk_param *par)
{
	struct nf_conntrack_helper *helper;
	struct nf_conn_help *help;
	u8 proto;

	proto = xt_ct_find_proto(par);
	if (!proto) {
		pr_info_ratelimited("You must specify a L4 protocol and not use inversions on it\n");
		return -ENOENT;
	}

	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
						    proto);
	if (helper == NULL) {
		pr_info_ratelimited("No such helper \"%s\"\n", helper_name);
		return -ENOENT;
	}

	help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
	if (help == NULL) {
		nf_conntrack_helper_put(helper);
		return -ENOMEM;
	}

	rcu_assign_pointer(help->helper, helper);
	return 0;
}

static int
xt_ct_set_timeout(struct nf_conn *ct, const struct xt_tgchk_param *par,
		  const char *timeout_name)
{
#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
	const struct nf_conntrack_l4proto *l4proto;
	u8 proto;

	proto = xt_ct_find_proto(par);
	if (!proto) {
		pr_info_ratelimited("You must specify a L4 protocol and not "
				    "use inversions on it");
		return -EINVAL;
	}
	l4proto = nf_ct_l4proto_find(proto);
	return nf_ct_set_timeout(par->net, ct, par->family, l4proto->l4proto,
				 timeout_name);

#else
	return -EOPNOTSUPP;
#endif
}

static u16 xt_ct_flags_to_dir(const struct xt_ct_target_info_v1 *info)
{
	switch (info->flags & (XT_CT_ZONE_DIR_ORIG |
			       XT_CT_ZONE_DIR_REPL)) {
	case XT_CT_ZONE_DIR_ORIG:
		return NF_CT_ZONE_DIR_ORIG;
	case XT_CT_ZONE_DIR_REPL:
		return NF_CT_ZONE_DIR_REPL;
	default:
		return NF_CT_DEFAULT_ZONE_DIR;
	}
}

static void xt_ct_put_helper(struct nf_conn_help *help)
{
	struct nf_conntrack_helper *helper;

	if (!help)
		return;

	/* not yet exposed to other cpus, or ruleset
	 * already detached (post-replacement).
	 */
	helper = rcu_dereference_raw(help->helper);
	if (helper)
		nf_conntrack_helper_put(helper);
}

static int xt_ct_tg_check(const struct xt_tgchk_param *par,
			  struct xt_ct_target_info_v1 *info)
{
	struct nf_conntrack_zone zone;
	struct nf_conn_help *help;
	struct nf_conn *ct;
	int ret = -EOPNOTSUPP;

	if (info->flags & XT_CT_NOTRACK) {
		ct = NULL;
		goto out;
	}

#ifndef CONFIG_NF_CONNTRACK_ZONES
	if (info->zone || info->flags & (XT_CT_ZONE_DIR_ORIG |
					 XT_CT_ZONE_DIR_REPL |
					 XT_CT_ZONE_MARK))
		goto err1;
#endif

	ret = nf_ct_netns_get(par->net, par->family);
	if (ret < 0)
		goto err1;

	memset(&zone, 0, sizeof(zone));
	zone.id = info->zone;
	zone.dir = xt_ct_flags_to_dir(info);
	if (info->flags & XT_CT_ZONE_MARK)
		zone.flags |= NF_CT_FLAG_MARK;

	ct = nf_ct_tmpl_alloc(par->net, &zone, GFP_KERNEL);
	if (!ct) {
		ret = -ENOMEM;
		goto err2;
	}

	if ((info->ct_events || info->exp_events) &&
	    !nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
				  GFP_KERNEL)) {
		ret = -EINVAL;
		goto err3;
	}

	if (info->helper[0]) {
		if (strnlen(info->helper, sizeof(info->helper)) == sizeof(info->helper)) {
			ret = -ENAMETOOLONG;
			goto err3;
		}

		ret = xt_ct_set_helper(ct, info->helper, par);
		if (ret < 0)
			goto err3;
	}

	if (info->timeout[0]) {
		if (strnlen(info->timeout, sizeof(info->timeout)) == sizeof(info->timeout)) {
			ret = -ENAMETOOLONG;
			goto err4;
		}

		ret = xt_ct_set_timeout(ct, par, info->timeout);
		if (ret < 0)
			goto err4;
	}
	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
out:
	info->ct = ct;
	return 0;

err4:
	help = nfct_help(ct);
	xt_ct_put_helper(help);
err3:
	nf_ct_tmpl_free(ct);
err2:
	nf_ct_netns_put(par->net, par->family);
err1:
	return ret;
}

static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info *info = par->targinfo;
	struct xt_ct_target_info_v1 info_v1 = {
		.flags 		= info->flags,
		.zone		= info->zone,
		.ct_events	= info->ct_events,
		.exp_events	= info->exp_events,
	};
	int ret;

	if (info->flags & ~XT_CT_NOTRACK)
		return -EINVAL;

	memcpy(info_v1.helper, info->helper, sizeof(info->helper));

	ret = xt_ct_tg_check(par, &info_v1);
	if (ret < 0)
		return ret;

	info->ct = info_v1.ct;

	return ret;
}

static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info_v1 *info = par->targinfo;

	if (info->flags & ~XT_CT_NOTRACK)
		return -EINVAL;

	return xt_ct_tg_check(par, par->targinfo);
}

static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
{
	struct xt_ct_target_info_v1 *info = par->targinfo;

	if (info->flags & ~XT_CT_MASK)
		return -EINVAL;

	return xt_ct_tg_check(par, par->targinfo);
}

static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
			     struct xt_ct_target_info_v1 *info)
{
	struct nf_conn *ct = info->ct;
	struct nf_conn_help *help;

	if (ct) {
		help = nfct_help(ct);
		xt_ct_put_helper(help);

		nf_ct_netns_put(par->net, par->family);

		nf_ct_destroy_timeout(ct);
		nf_ct_put(info->ct);
	}
}

static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
{
	struct xt_ct_target_info *info = par->targinfo;
	struct xt_ct_target_info_v1 info_v1 = {
		.flags 		= info->flags,
		.zone		= info->zone,
		.ct_events	= info->ct_events,
		.exp_events	= info->exp_events,
		.ct		= info->ct,
	};
	memcpy(info_v1.helper, info->helper, sizeof(info->helper));

	xt_ct_tg_destroy(par, &info_v1);
}

static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
{
	xt_ct_tg_destroy(par, par->targinfo);
}

static struct xt_target xt_ct_tg_reg[] __read_mostly = {
	{
		.name		= "CT",
		.family		= NFPROTO_UNSPEC,
		.targetsize	= sizeof(struct xt_ct_target_info),
		.usersize	= offsetof(struct xt_ct_target_info, ct),
		.checkentry	= xt_ct_tg_check_v0,
		.destroy	= xt_ct_tg_destroy_v0,
		.target		= xt_ct_target_v0,
		.table		= "raw",
		.me		= THIS_MODULE,
	},
	{
		.name		= "CT",
		.family		= NFPROTO_UNSPEC,
		.revision	= 1,
		.targetsize	= sizeof(struct xt_ct_target_info_v1),
		.usersize	= offsetof(struct xt_ct_target_info, ct),
		.checkentry	= xt_ct_tg_check_v1,
		.destroy	= xt_ct_tg_destroy_v1,
		.target		= xt_ct_target_v1,
		.table		= "raw",
		.me		= THIS_MODULE,
	},
	{
		.name		= "CT",
		.family		= NFPROTO_UNSPEC,
		.revision	= 2,
		.targetsize	= sizeof(struct xt_ct_target_info_v1),
		.usersize	= offsetof(struct xt_ct_target_info, ct),
		.checkentry	= xt_ct_tg_check_v2,
		.destroy	= xt_ct_tg_destroy_v1,
		.target		= xt_ct_target_v1,
		.table		= "raw",
		.me		= THIS_MODULE,
	},
};

static unsigned int
notrack_tg(struct sk_buff *skb, const struct xt_action_param *par)
{
	/* Previously seen (loopback)? Ignore. */
	if (skb->_nfct != 0)
		return XT_CONTINUE;

	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);

	return XT_CONTINUE;
}

static struct xt_target notrack_tg_reg __read_mostly = {
	.name		= "NOTRACK",
	.revision	= 0,
	.family		= NFPROTO_UNSPEC,
	.target		= notrack_tg,
	.table		= "raw",
	.me		= THIS_MODULE,
};

static int __init xt_ct_tg_init(void)
{
	int ret;

	ret = xt_register_target(&notrack_tg_reg);
	if (ret < 0)
		return ret;

	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
	if (ret < 0) {
		xt_unregister_target(&notrack_tg_reg);
		return ret;
	}
	return 0;
}

static void __exit xt_ct_tg_exit(void)
{
	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
	xt_unregister_target(&notrack_tg_reg);
}

module_init(xt_ct_tg_init);
module_exit(xt_ct_tg_exit);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("Xtables: connection tracking target");
MODULE_ALIAS("ipt_CT");
MODULE_ALIAS("ip6t_CT");
MODULE_ALIAS("ipt_NOTRACK");
MODULE_ALIAS("ip6t_NOTRACK");
Commit	Line	Data
d2912cb1	1	// SPDX-License-Identifier: GPL-2.0-only
84f3bb9a PM	2	/*
84f3bb9a PM	3	* Copyright (c) 2010 Patrick McHardy <kaber@trash.net>
84f3bb9a	4	*/
a7fed762	5	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
84f3bb9a	6	#include <linux/module.h>
5a0e3ad6	7	#include <linux/gfp.h>
84f3bb9a	8	#include <linux/skbuff.h>
84f3bb9a PM	9	#include <linux/netfilter_ipv4/ip_tables.h>
	10	#include <linux/netfilter_ipv6/ip6_tables.h>
	11	#include <linux/netfilter/x_tables.h>
	12	#include <linux/netfilter/xt_CT.h>
	13	#include <net/netfilter/nf_conntrack.h>
eeb4cb95	14	#include <net/netfilter/nf_conntrack_l4proto.h>
84f3bb9a PM	15	#include <net/netfilter/nf_conntrack_helper.h>
84f3bb9a PM	16	#include <net/netfilter/nf_conntrack_ecache.h>
24de58f4	17	#include <net/netfilter/nf_conntrack_timeout.h>
5d0aa2cc	18	#include <net/netfilter/nf_conntrack_zones.h>
84f3bb9a	19
d52ed437	20	static inline int xt_ct_target(struct sk_buff skb, struct nf_conn ct)
84f3bb9a	21	{
84f3bb9a	22	/* Previously seen (loopback)? Ignore. */
a9e419dc	23	if (skb->_nfct != 0)
84f3bb9a PM	24	return XT_CONTINUE;
84f3bb9a PM	25
cc41c84b	26	if (ct) {
71977437	27	refcount_inc(&ct->ct_general.use);
cc41c84b FW	28	nf_ct_set(skb, ct, IP_CT_NEW);
	29	} else {
	30	nf_ct_set(skb, ct, IP_CT_UNTRACKED);
	31	}
84f3bb9a PM	32
	33	return XT_CONTINUE;
	34	}
	35
d52ed437	36	static unsigned int xt_ct_target_v0(struct sk_buff *skb,
24de58f4 PNA	37	const struct xt_action_param *par)
24de58f4 PNA	38	{
d52ed437	39	const struct xt_ct_target_info *info = par->targinfo;
24de58f4 PNA	40	struct nf_conn *ct = info->ct;
24de58f4 PNA	41
d52ed437 PNA	42	return xt_ct_target(skb, ct);
d52ed437 PNA	43	}
24de58f4	44
d52ed437 PNA	45	static unsigned int xt_ct_target_v1(struct sk_buff *skb,
	46	const struct xt_action_param *par)
	47	{
	48	const struct xt_ct_target_info_v1 *info = par->targinfo;
	49	struct nf_conn *ct = info->ct;
24de58f4	50
d52ed437	51	return xt_ct_target(skb, ct);
24de58f4 PNA	52	}
24de58f4 PNA	53
84f3bb9a PM	54	static u8 xt_ct_find_proto(const struct xt_tgchk_param *par)
84f3bb9a PM	55	{
076f7839	56	if (par->family == NFPROTO_IPV4) {
84f3bb9a PM	57	const struct ipt_entry *e = par->entryinfo;
	58
	59	if (e->ip.invflags & IPT_INV_PROTO)
	60	return 0;
	61	return e->ip.proto;
076f7839	62	} else if (par->family == NFPROTO_IPV6) {
84f3bb9a PM	63	const struct ip6t_entry *e = par->entryinfo;
	64
	65	if (e->ipv6.invflags & IP6T_INV_PROTO)
	66	return 0;
	67	return e->ipv6.proto;
	68	} else
	69	return 0;
	70	}
	71
236df005 PNA	72	static int
	73	xt_ct_set_helper(struct nf_conn ct, const char helper_name,
	74	const struct xt_tgchk_param *par)
	75	{
	76	struct nf_conntrack_helper *helper;
	77	struct nf_conn_help *help;
	78	u8 proto;
	79
	80	proto = xt_ct_find_proto(par);
	81	if (!proto) {
11f7aee2	82	pr_info_ratelimited("You must specify a L4 protocol and not use inversions on it\n");
236df005 PNA	83	return -ENOENT;
	84	}
	85
	86	helper = nf_conntrack_helper_try_module_get(helper_name, par->family,
	87	proto);
	88	if (helper == NULL) {
11f7aee2	89	pr_info_ratelimited("No such helper \"%s\"\n", helper_name);
236df005 PNA	90	return -ENOENT;
	91	}
	92
440534d3	93	help = nf_ct_helper_ext_add(ct, GFP_KERNEL);
236df005	94	if (help == NULL) {
d91fc59c	95	nf_conntrack_helper_put(helper);
236df005 PNA	96	return -ENOMEM;
	97	}
	98
e14575fa	99	rcu_assign_pointer(help->helper, helper);
236df005 PNA	100	return 0;
	101	}
	102
236df005 PNA	103	static int
	104	xt_ct_set_timeout(struct nf_conn ct, const struct xt_tgchk_param par,
	105	const char *timeout_name)
	106	{
	107	#ifdef CONFIG_NF_CONNTRACK_TIMEOUT
b3480fe0	108	const struct nf_conntrack_l4proto *l4proto;
0153d5a8	109	u8 proto;
236df005	110
0153d5a8 PNA	111	proto = xt_ct_find_proto(par);
0153d5a8 PNA	112	if (!proto) {
717700d1 YHW	113	pr_info_ratelimited("You must specify a L4 protocol and not "
	114	"use inversions on it");
	115	return -EINVAL;
236df005	116	}
4a60dc74	117	l4proto = nf_ct_l4proto_find(proto);
717700d1 YHW	118	return nf_ct_set_timeout(par->net, ct, par->family, l4proto->l4proto,
717700d1 YHW	119	timeout_name);
236df005	120
236df005 PNA	121	#else
	122	return -EOPNOTSUPP;
	123	#endif
	124	}
	125
deedb590 DB	126	static u16 xt_ct_flags_to_dir(const struct xt_ct_target_info_v1 *info)
	127	{
	128	switch (info->flags & (XT_CT_ZONE_DIR_ORIG \|
	129	XT_CT_ZONE_DIR_REPL)) {
	130	case XT_CT_ZONE_DIR_ORIG:
	131	return NF_CT_ZONE_DIR_ORIG;
	132	case XT_CT_ZONE_DIR_REPL:
	133	return NF_CT_ZONE_DIR_REPL;
	134	default:
	135	return NF_CT_DEFAULT_ZONE_DIR;
	136	}
	137	}
	138
e14575fa FW	139	static void xt_ct_put_helper(struct nf_conn_help *help)
	140	{
	141	struct nf_conntrack_helper *helper;
	142
	143	if (!help)
	144	return;
	145
	146	/* not yet exposed to other cpus, or ruleset
	147	* already detached (post-replacement).
	148	*/
	149	helper = rcu_dereference_raw(help->helper);
	150	if (helper)
	151	nf_conntrack_helper_put(helper);
	152	}
	153
d52ed437 PNA	154	static int xt_ct_tg_check(const struct xt_tgchk_param *par,
d52ed437 PNA	155	struct xt_ct_target_info_v1 *info)
24de58f4	156	{
308ac914	157	struct nf_conntrack_zone zone;
470acf55	158	struct nf_conn_help *help;
24de58f4	159	struct nf_conn *ct;
4610476d	160	int ret = -EOPNOTSUPP;
236df005	161
24de58f4	162	if (info->flags & XT_CT_NOTRACK) {
27e7190e	163	ct = NULL;
24de58f4 PNA	164	goto out;
	165	}
	166
	167	#ifndef CONFIG_NF_CONNTRACK_ZONES
deedb590	168	if (info->zone \|\| info->flags & (XT_CT_ZONE_DIR_ORIG \|
5e8018fc DB	169	XT_CT_ZONE_DIR_REPL \|
5e8018fc DB	170	XT_CT_ZONE_MARK))
24de58f4 PNA	171	goto err1;
	172	#endif
	173
ecb2421b	174	ret = nf_ct_netns_get(par->net, par->family);
24de58f4 PNA	175	if (ret < 0)
	176	goto err1;
	177
308ac914 DB	178	memset(&zone, 0, sizeof(zone));
308ac914 DB	179	zone.id = info->zone;
deedb590	180	zone.dir = xt_ct_flags_to_dir(info);
5e8018fc DB	181	if (info->flags & XT_CT_ZONE_MARK)
5e8018fc DB	182	zone.flags \|= NF_CT_FLAG_MARK;
308ac914 DB	183
308ac914 DB	184	ct = nf_ct_tmpl_alloc(par->net, &zone, GFP_KERNEL);
1a727c63 DC	185	if (!ct) {
1a727c63 DC	186	ret = -ENOMEM;
24de58f4	187	goto err2;
1a727c63	188	}
24de58f4	189
24de58f4 PNA	190	if ((info->ct_events \|\| info->exp_events) &&
24de58f4 PNA	191	!nf_ct_ecache_ext_add(ct, info->ct_events, info->exp_events,
14abfa16 EL	192	GFP_KERNEL)) {
14abfa16 EL	193	ret = -EINVAL;
24de58f4	194	goto err3;
14abfa16	195	}
24de58f4 PNA	196
24de58f4 PNA	197	if (info->helper[0]) {
8f4d19aa GF	198	if (strnlen(info->helper, sizeof(info->helper)) == sizeof(info->helper)) {
	199	ret = -ENAMETOOLONG;
	200	goto err3;
	201	}
	202
236df005 PNA	203	ret = xt_ct_set_helper(ct, info->helper, par);
236df005 PNA	204	if (ret < 0)
1afc5679	205	goto err3;
24de58f4 PNA	206	}
24de58f4 PNA	207
6cf51852	208	if (info->timeout[0]) {
8f4d19aa GF	209	if (strnlen(info->timeout, sizeof(info->timeout)) == sizeof(info->timeout)) {
	210	ret = -ENAMETOOLONG;
	211	goto err4;
	212	}
	213
236df005 PNA	214	ret = xt_ct_set_timeout(ct, par, info->timeout);
236df005 PNA	215	if (ret < 0)
470acf55	216	goto err4;
24de58f4	217	}
0838aa7f	218	__set_bit(IPS_CONFIRMED_BIT, &ct->status);
24de58f4 PNA	219	out:
	220	info->ct = ct;
	221	return 0;
	222
470acf55 GF	223	err4:
470acf55 GF	224	help = nfct_help(ct);
e14575fa	225	xt_ct_put_helper(help);
24de58f4	226	err3:
9cf94eab	227	nf_ct_tmpl_free(ct);
24de58f4	228	err2:
ecb2421b	229	nf_ct_netns_put(par->net, par->family);
24de58f4 PNA	230	err1:
	231	return ret;
	232	}
	233
d52ed437	234	static int xt_ct_tg_check_v0(const struct xt_tgchk_param *par)
84f3bb9a PM	235	{
84f3bb9a PM	236	struct xt_ct_target_info *info = par->targinfo;
d52ed437 PNA	237	struct xt_ct_target_info_v1 info_v1 = {
	238	.flags = info->flags,
	239	.zone = info->zone,
	240	.ct_events = info->ct_events,
	241	.exp_events = info->exp_events,
	242	};
	243	int ret;
84f3bb9a	244
5474f57f PNA	245	if (info->flags & ~XT_CT_NOTRACK)
	246	return -EINVAL;
	247
d52ed437	248	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
84f3bb9a	249
d52ed437 PNA	250	ret = xt_ct_tg_check(par, &info_v1);
	251	if (ret < 0)
	252	return ret;
	253
	254	info->ct = info_v1.ct;
	255
	256	return ret;
	257	}
	258
	259	static int xt_ct_tg_check_v1(const struct xt_tgchk_param *par)
	260	{
5474f57f PNA	261	struct xt_ct_target_info_v1 *info = par->targinfo;
	262
	263	if (info->flags & ~XT_CT_NOTRACK)
	264	return -EINVAL;
	265
	266	return xt_ct_tg_check(par, par->targinfo);
	267	}
	268
	269	static int xt_ct_tg_check_v2(const struct xt_tgchk_param *par)
	270	{
	271	struct xt_ct_target_info_v1 *info = par->targinfo;
	272
	273	if (info->flags & ~XT_CT_MASK)
	274	return -EINVAL;
	275
d52ed437	276	return xt_ct_tg_check(par, par->targinfo);
84f3bb9a PM	277	}
84f3bb9a PM	278
d52ed437 PNA	279	static void xt_ct_tg_destroy(const struct xt_tgdtor_param *par,
d52ed437 PNA	280	struct xt_ct_target_info_v1 *info)
236df005	281	{
236df005 PNA	282	struct nf_conn *ct = info->ct;
	283	struct nf_conn_help *help;
	284
cc41c84b	285	if (ct) {
24de58f4	286	help = nfct_help(ct);
e14575fa	287	xt_ct_put_helper(help);
24de58f4	288
ecb2421b	289	nf_ct_netns_put(par->net, par->family);
24de58f4	290
717700d1	291	nf_ct_destroy_timeout(ct);
27e7190e	292	nf_ct_put(info->ct);
24de58f4	293	}
d52ed437 PNA	294	}
	295
	296	static void xt_ct_tg_destroy_v0(const struct xt_tgdtor_param *par)
	297	{
	298	struct xt_ct_target_info *info = par->targinfo;
	299	struct xt_ct_target_info_v1 info_v1 = {
	300	.flags = info->flags,
	301	.zone = info->zone,
	302	.ct_events = info->ct_events,
	303	.exp_events = info->exp_events,
	304	.ct = info->ct,
	305	};
	306	memcpy(info_v1.helper, info->helper, sizeof(info->helper));
	307
	308	xt_ct_tg_destroy(par, &info_v1);
	309	}
	310
	311	static void xt_ct_tg_destroy_v1(const struct xt_tgdtor_param *par)
	312	{
	313	xt_ct_tg_destroy(par, par->targinfo);
24de58f4 PNA	314	}
	315
	316	static struct xt_target xt_ct_tg_reg[] __read_mostly = {
	317	{
	318	.name = "CT",
	319	.family = NFPROTO_UNSPEC,
	320	.targetsize = sizeof(struct xt_ct_target_info),
ec231890	321	.usersize = offsetof(struct xt_ct_target_info, ct),
24de58f4 PNA	322	.checkentry = xt_ct_tg_check_v0,
	323	.destroy = xt_ct_tg_destroy_v0,
	324	.target = xt_ct_target_v0,
	325	.table = "raw",
	326	.me = THIS_MODULE,
	327	},
	328	{
	329	.name = "CT",
	330	.family = NFPROTO_UNSPEC,
	331	.revision = 1,
	332	.targetsize = sizeof(struct xt_ct_target_info_v1),
ec231890	333	.usersize = offsetof(struct xt_ct_target_info, ct),
24de58f4 PNA	334	.checkentry = xt_ct_tg_check_v1,
	335	.destroy = xt_ct_tg_destroy_v1,
	336	.target = xt_ct_target_v1,
	337	.table = "raw",
	338	.me = THIS_MODULE,
	339	},
5474f57f PNA	340	{
	341	.name = "CT",
	342	.family = NFPROTO_UNSPEC,
	343	.revision = 2,
	344	.targetsize = sizeof(struct xt_ct_target_info_v1),
ec231890	345	.usersize = offsetof(struct xt_ct_target_info, ct),
5474f57f PNA	346	.checkentry = xt_ct_tg_check_v2,
	347	.destroy = xt_ct_tg_destroy_v1,
	348	.target = xt_ct_target_v1,
	349	.table = "raw",
	350	.me = THIS_MODULE,
	351	},
84f3bb9a PM	352	};
84f3bb9a PM	353
10db9069 PNA	354	static unsigned int
	355	notrack_tg(struct sk_buff skb, const struct xt_action_param par)
	356	{
	357	/* Previously seen (loopback)? Ignore. */
a9e419dc	358	if (skb->_nfct != 0)
10db9069 PNA	359	return XT_CONTINUE;
10db9069 PNA	360
cc41c84b	361	nf_ct_set(skb, NULL, IP_CT_UNTRACKED);
10db9069 PNA	362
	363	return XT_CONTINUE;
	364	}
	365
10db9069 PNA	366	static struct xt_target notrack_tg_reg __read_mostly = {
	367	.name = "NOTRACK",
	368	.revision = 0,
	369	.family = NFPROTO_UNSPEC,
10db9069 PNA	370	.target = notrack_tg,
	371	.table = "raw",
	372	.me = THIS_MODULE,
	373	};
	374
84f3bb9a PM	375	static int __init xt_ct_tg_init(void)
84f3bb9a PM	376	{
10db9069 PNA	377	int ret;
	378
	379	ret = xt_register_target(&notrack_tg_reg);
	380	if (ret < 0)
	381	return ret;
	382
	383	ret = xt_register_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
	384	if (ret < 0) {
	385	xt_unregister_target(&notrack_tg_reg);
	386	return ret;
	387	}
	388	return 0;
84f3bb9a PM	389	}
	390
	391	static void __exit xt_ct_tg_exit(void)
	392	{
24de58f4	393	xt_unregister_targets(xt_ct_tg_reg, ARRAY_SIZE(xt_ct_tg_reg));
10db9069	394	xt_unregister_target(&notrack_tg_reg);
84f3bb9a PM	395	}
	396
	397	module_init(xt_ct_tg_init);
	398	module_exit(xt_ct_tg_exit);
	399
	400	MODULE_LICENSE("GPL");
	401	MODULE_DESCRIPTION("Xtables: connection tracking target");
	402	MODULE_ALIAS("ipt_CT");
	403	MODULE_ALIAS("ip6t_CT");
10db9069 PNA	404	MODULE_ALIAS("ipt_NOTRACK");
10db9069 PNA	405	MODULE_ALIAS("ip6t_NOTRACK");